Is it possible to change HTML font size after converting? (not manually)

I have been importing articles as .md and converting them into HTML However the final product becomes too little to read.

Is there a possible to change the font size after importing/converting? My guess would be Preferences > Web > Style sheet but I haven’t been lucky so far. I would like to avoid doing manually every time by using the editor and increasing the font size.

Thanks!

What exactly did you try with the style sheet setting and what did (not) work?

If you’re not using a default style sheet, the font used is from Preferences > Editing > Rich Text & Note Font.

This is noted in the Help > Documenation > Documents > Markdown Documents